YOU SAID:
I need to sleep tomorrow, so I will sleep today
INTO JAPANESE
明日は寝たいので今日は寝ます
BACK INTO ENGLISH
I want to sleep tomorrow, so I will sleep today.
INTO JAPANESE
明日寝たいので今日は寝ます。
BACK INTO ENGLISH
I'm going to sleep today because I want to sleep tomorrow.
INTO JAPANESE
明日寝たいので今日は寝ます。
BACK INTO ENGLISH
I'm going to sleep today because I want to sleep tomorrow.
That didn't even make that much sense in English.